Bibcode
Villar Martín, M.; Bellocchi, E.; Stern, J.; Ramos Almeida, C.; Tadhunter, C.; González Delgado, R.
Bibliographical reference
Monthly Notices of the Royal Astronomical Society, Volume 454, Issue 1, p.439-456
Advertised on:
11
2015
Citations
21
Refereed citations
21
Description
We study the physical and kinematic properties of the narrow-line region
(NLR) of the nearest obscured quasar MRK 477 (z = 0.037), using optical
and near-infrared (NIR) spectroscopy. About 100 emission lines are
identified in the optical+NIR spectrum (90 in the optical), including
several narrow optical Fe+ lines. To our knowledge, this is
the first type 2 active galactic nucleus (AGN) with such a detection.
The Fe+ lines can be explained as the natural emission from
the NLR photoionized by the AGN. Coronal line emission can only be
confirmed in the NIR spectrum. As in many other AGNs, a significant
correlation is found between the lines' full width at half-maximum and
the critical density log(ncrit). We propose that it is caused
by the outflow. This could be the case in other AGNs. The nuclear
jet-induced ionized outflow has been kinematically isolated in many
emission lines covering a broad range of ionization potentials and
critical densities. It is concentrated within R ˜few×100 pc
from the central engine. The outflowing gas is denser (n ≳ 8000
cm-3) than the ambient non-perturbed gas (n ˜ 400-630
cm-3). This could be due to the compression effect of the
jet-induced shocks. Alternatively, we propose that the outflow has been
triggered by the jet at R ≲ 220 pc (possibly at ≲ 30 pc), and
we trace how the impact weakens as it propagates outwards following the
radiation-pressure-dominated density gradient. The different kinematic
behaviour of [Fe II] λ1.644 μm suggests that its emission is
enhanced by shocks induced by the nuclear outflow/jet and is
preferentially emitted at a different, less reddened spatial location.
Related projects
Nuclear Activity in Galaxies: a 3D Perspective from the Nucleus to the Outskirts
This project consists of two main research lines. First, the study of quasar-driven outflows in luminous and nearby obscured active galactic nuclei (AGN) and the impact that they have on their massive host galaxies (AGN feedback). To do so, we have obtained Gran Telescopio CANARIAS (GTC) infrared and optical observations with the instruments
Cristina
Ramos Almeida